1. Field of the Invention
The present invention relates to an actuating drive for a pneumatic valve of a revolver type movable insertion head for placing electrical components on to a components carrier. The insertion head includes a stator and a rotor mounted thereat which can be driven in an indexed fashion and which is provided with a plurality of suction pipettes for the components wherein the pipettes protrude in a circular fashion and are successively rotatable into a placement attitude.
2. Description of the Prior Art
DE 196 04 603 C2 teaches a revolver head in which a control valve is allocated to each suction pipette for changing the pressure relations in the suction pipette. A valve drive is anchored at the stator of the insertion head wherein the drive becomes engaged with displaceable control parts of the valve; this being exactly in the placement attitude. The valve drive consists of a stepping motor at whose primary shaft a crankshaft journal with a rolling bearing is provided. The journal projects between two radially protruding cross-ribs of a control slide of the valve wherein the slide attitude can be displaced through a changing of the rotary position of the crankshaft journal. The outer diameter of the rolling bearing is considerably smaller than the distance between the cross-ribs in order to enable return stroke of the crankshaft journal. In the swinging of the suction pipettes into the placement attitude, the crankshaft journal arrives between the two cross-ribs wherein there is no problem in mutual attitudinal adjustment as a result of the large curvature of the rolling bearing and of the lateral play to the cross-ribs.